Enegy Sources

Question 1

Primary energy source

Answer 1

an energy source, such as coal, wind, oil, gas, or water, which is used directly by the consumer.

Question 2

Expectancy formula

Answer 2

Reserves / production

Question 3

Secondary energy source

Answer 3

A secondary energy source is an energy source, such as electricity or hydrogen, which has been transformed from a primary energy source before use by the consumer.

Question 4

Specific energy

Answer 4

Specific energy is how much energy you can get per unit mass from a fuel. It’s units are J kg

Question 5

Energy density

Answer 5

Energy you can get per unit volume. It’s units are J m-3

Question 6

Renewable resources

Answer 6

Can be replenished within a human lifetime ( or does not run out )

Question 7

What is better oil and gas or coal ?

Answer 7

Oil and gas are better because they burn more efficiently and produce less co2 ( howver cola is cheaper and more plentiful )

Question 8

Efficiency formula

Answer 8

Useful energy output / energy input

Question 9

Fossil fuels advantages (3)

Answer 9

Readily available, relatively cheaper and not reliant upon the weather

Question 10

Most common way to generate electricity is

Answer 10

Coal burning power plant

Question 11

Nuclear fission

Answer 11

Splitting of atoms of a nucleur fuel to release large amounts of heat energy

Question 12

Main advantage of nucleur power

Answer 12

Radioactive waste is produced. This can be very dangerous and difficult to dispose of

Question 13

Units for energy

Answer 13

Jpules

Question 14

Absorption

Answer 14

Energy is absorbed by atoms ( incraeses kinetic energy )

Question 15

Reflection of energy

Answer 15

Energy is not absorbed but is rather reflected back along its path

Question 16

Emission

Answer 16

Energy is absorbed and then released again ( given out again ) . When emitted properties fo teh energy would have changed

Question 17

Degree of change by teh green house effect ( normally )

Answer 17

Makes earths temperatures around 33 degrees higher than it would otherwise be

Question 18

Some examples of greenhouse gasses ( 5)

Answer 18

Methane, carbon dioxide, nitrous oxide! Water vapor, ozone

Question 19

Tehrmal radiation includes ?

Answer 19

Infrared waves and visible light

Question 20

Energy reaches us from teh sun is teh form of ?

Answer 20

Electromagnetic radiation

Question 21

Why do hot objects seem to glow ?

Answer 21

Warm objects give out infrared radiation. As objects become hotter, so they begin to give out shorter wavelengths such as light. This is why hot objects, such as metals (toaster element/ cooking grills) glow as they continue to heat up.

Question 22

Hwo is absorption of colors decided

Answer 22

Thermometers are attached to teh rear of metal pleases which are placed at equal distances form teh radiant heater,. Tehrmal energy from teh radiant heater is absorbed by teh two plates , and teh thermometer helps us asses which color is the best abosirber

Question 23

Absorptivity

Answer 23

Measure of how much of teh radiation is absorbed by teh body

Question 24

Transmissivity

Answer 24

Measure of how much radiation passes through teh object

Question 25

Emmisivity

Answer 25

Measure of how much thermal radiation a body emits to its environment

Question 26

Balck body

Answer 26

Ideal object taht ahs perfect absorption of all radiation taht falls on it

0 reflectivity and transmissivity

Question 27

Hwo is black body radiation generated

Answer 27

Oscillating le rice charges in Teh atoms of teh body

Question 28

Albedo

Answer 28

Albedo is the amount of sunlight (solar radiation) reflected by a surface

Question 29

Albedo formula

Answer 29

Tottal scattered power/total incident value

Question 30

Solar Irradation

Answer 30

Amount of electromagnetic radiation received from teh sun per unit are ( normally square meter )

Question 31

Geothermal energy advantages

Answer 31

free, renewable energy source. No real environmental problems.

Question 32

Geothermal energy disadvantages

Answer 32

cost of drilling down several km to the hot rocks.
Not available everywhere ( very few places )

Question 33

Where is geothermal energy used

Answer 33

Used where hot rocks lie quite near to the surface. Cold water is pumped in pipes down to the hot rocks, and returns as steam to drive the turbines.

Question 34

Biofuels advantages

Answer 34

relatively quick and natural sources of energy and are considered to be carbon neutral (do not release additional carbon dioxide into the atmosphere).

Question 35

Biofuel disadvantages

Answer 35

natural habitats may be cleared to make way for biofuel crops, and some food crops may be lost.

Question 36

What are biofuels

Answer 36

Biofuels are renewable energy sources. They can be solids (eg. Straw, woodchip), liquids (eg. Ethanol) or gases (eg. Methane biogas from sludge digesters).

Question 37

How are biofuels used

Answer 37

They are burnt to turn water into steam, which drives the turbine and producing electricity in the generator.

Question 38

Solar panels advantages

Answer 38

Advantages: nopollution,averyreliable source in sunny countries. Energy is free, and running costs are almost nil.

Question 39

Solar panels disadvantages

Answer 39

Only heats water in daytime. Not used to produce electricity.

Question 40

Photovoltaics ( what is it made out of )

Answer 40

The cell is made of crystalline silicon (a semiconductor) doped with phosphorus and boron impurities.

Question 41

Solar CELLS advantages

Answer 41

nopollution,averyreliable source in sunny countries. Energy is free, and running costs are almost nil. ( main Tempe is extremely low ), long life ( industrial use 25 - 30 years )

Question 42

Solar cell disadvantages

Answer 42

Devolping technology, very high initial cost, lots of soace needed

Question 43

Wave power advantages

Answer 43

no pollution, no fuel costs, minimal running costs. Can be very useful on small islands.

Question 44

Wave power disadvantages

Answer 44

hazard to boats, can be an eyesore, fairly unreliable as waves disappear when the wind drops, initial costs can be very high, environmental impact.

Question 45

How does wave power work

Answer 45

As waves come in to the shore they provide up and down motion which can be used to directly drive a turbine which is linked to a generator.
The waves force the air through the turbine, causing it to spin.